As a supplier of oil-immersed transformers, I often encounter inquiries from customers regarding the types of oil used in these essential electrical devices. The choice of oil is crucial as it significantly impacts the performance, reliability, and lifespan of the transformer. In this blog post, I will delve into the various types of oil commonly used in oil-immersed transformers, their characteristics, advantages, and limitations. Oil Immersed Transformer
Mineral Oil
Mineral oil is the most widely used insulating fluid in oil-immersed transformers due to its excellent electrical insulating properties, high dielectric strength, and relatively low cost. It is a petroleum-based product derived from crude oil through a refining process. Mineral oil offers several key benefits:
Electrical Insulation
Mineral oil has a high dielectric strength, which means it can withstand high voltages without breaking down. This property is essential for preventing electrical arcing and short circuits within the transformer, ensuring safe and reliable operation.
Cooling
Mineral oil has good heat transfer properties, allowing it to effectively dissipate heat generated by the transformer’s core and windings. This helps to maintain the transformer’s temperature within acceptable limits, preventing overheating and extending its lifespan.
Chemical Stability
Mineral oil is chemically stable and resistant to oxidation and degradation, even under high temperatures and electrical stresses. This ensures long-term performance and reliability of the transformer.
However, mineral oil also has some limitations. It is flammable, which poses a potential fire hazard in the event of a transformer failure. Additionally, mineral oil is not biodegradable, which can have environmental implications if it is released into the environment.
Silicone Oil
Silicone oil is another type of insulating fluid used in oil-immersed transformers, particularly in applications where fire safety and environmental concerns are paramount. Silicone oil is a synthetic fluid made from silicon, oxygen, carbon, and hydrogen atoms. It offers several advantages over mineral oil:
Fire Resistance
Silicone oil has a high flash point and is non-flammable, making it a safer alternative to mineral oil in applications where fire safety is a concern. This reduces the risk of fire and explosion in the event of a transformer failure.
Environmental Friendliness
Silicone oil is biodegradable and has a low environmental impact compared to mineral oil. It is also less toxic, which makes it a more sustainable choice for oil-immersed transformers.
Chemical Stability
Silicone oil is highly resistant to oxidation and degradation, even under extreme temperatures and electrical stresses. This ensures long-term performance and reliability of the transformer.
However, silicone oil is more expensive than mineral oil, which can make it less cost-effective for some applications. Additionally, silicone oil has lower heat transfer properties than mineral oil, which may require additional cooling measures to maintain the transformer’s temperature within acceptable limits.
Natural Ester Oil
Natural ester oil is a renewable and biodegradable insulating fluid made from vegetable oils, such as soybean, rapeseed, or sunflower oil. It is an environmentally friendly alternative to mineral oil and silicone oil, offering several advantages:
Environmental Friendliness
Natural ester oil is biodegradable and has a low environmental impact compared to mineral oil and silicone oil. It is also derived from renewable resources, making it a more sustainable choice for oil-immersed transformers.
Fire Resistance
Natural ester oil has a high flash point and is less flammable than mineral oil, which reduces the risk of fire and explosion in the event of a transformer failure.
Good Electrical Insulation
Natural ester oil has good electrical insulating properties, similar to mineral oil. It can withstand high voltages without breaking down, ensuring safe and reliable operation of the transformer.
However, natural ester oil also has some limitations. It is more expensive than mineral oil, which can make it less cost-effective for some applications. Additionally, natural ester oil has a higher viscosity than mineral oil, which may require additional cooling measures to maintain the transformer’s temperature within acceptable limits.
Synthetic Ester Oil
Synthetic ester oil is a man-made insulating fluid designed to offer the best of both worlds: the high performance of mineral oil and the environmental friendliness of natural ester oil. Synthetic ester oil is made from synthetic chemicals and offers several advantages:
Environmental Friendliness
Synthetic ester oil is biodegradable and has a low environmental impact compared to mineral oil. It is also less toxic, which makes it a more sustainable choice for oil-immersed transformers.
Fire Resistance
Synthetic ester oil has a high flash point and is less flammable than mineral oil, which reduces the risk of fire and explosion in the event of a transformer failure.
Good Electrical Insulation
Synthetic ester oil has excellent electrical insulating properties, similar to mineral oil. It can withstand high voltages without breaking down, ensuring safe and reliable operation of the transformer.
High Thermal Stability
Synthetic ester oil has a high thermal stability, which means it can operate at higher temperatures than mineral oil without degrading. This allows for more efficient operation of the transformer and extends its lifespan.
However, synthetic ester oil is more expensive than mineral oil, which can make it less cost-effective for some applications. Additionally, synthetic ester oil may require special handling and storage procedures due to its chemical properties.
Conclusion
The choice of oil used in oil-immersed transformers depends on several factors, including the application, performance requirements, fire safety, environmental concerns, and cost. Mineral oil is the most widely used insulating fluid due to its excellent electrical insulating properties, high dielectric strength, and relatively low cost. However, it is flammable and not biodegradable, which can have environmental implications. Silicone oil, natural ester oil, and synthetic ester oil offer alternative solutions that are more fire-resistant and environmentally friendly, but they are also more expensive.
As a supplier of oil-immersed transformers, we understand the importance of choosing the right oil for your specific application. Our team of experts can help you evaluate your needs and recommend the most suitable oil for your transformer. We offer a wide range of oil-immersed transformers filled with different types of oil to meet your requirements.
Power Transformer If you are interested in learning more about our oil-immersed transformers or have any questions about the types of oil used in them, please don’t hesitate to contact us. We are here to help you make an informed decision and ensure the reliable and efficient operation of your electrical system.
References
- IEEE Guide for Liquid-Immersed Transformer Through-Fault-Current Duration, IEEE Std C57.109-2018
- IEC 60296:2012 Mineral insulating oils for electrical equipment
- ASTM D3487 – 17 Standard Specification for Mineral Insulating Oil Used in Electrical Apparatus
- CIGRE Technical Brochure 675: Natural and synthetic esters for transformers – A review of the state – of – the – art
Henan GNEE Electric Co., Ltd.
Henan GNEE Electric Co., Ltd. is well-known as one of the leading oil immersed transformer manufacturers and suppliers in China. If you’re going to buy customized oil immersed transformer made in China, welcome to get pricelist from our factory. Quality products and low price are available.
Address: 25TH FLOOR HUAFU COMMERCIAL CENTER ANYANG HENAN CHINA.
E-mail: sales@gneesteels.com
WebSite: https://www.chinasiliconsteel.com/
